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SAE 5160 steel, classified as high-strength, low-alloy steel, is widely used in the automotive sector due to its excellent mechanical strength and ductility. However, its inherently low corrosion resistance limits its broader application. This study explores the application of the cathodic cage plasma deposition (CCPD) technique to enhance the corrosion resistance of SAE 5160 steel. The treatment was performed using a Hastelloy cathodic cage under two atmospheric conditions: hydrogen-rich (75%H2/25%N2) and nitrogen-rich (25%H2/75%N2). Comprehensive analyses revealed significant improvements in surface properties and corrosion resistance. The hydrogen-rich condition (H25N) facilitated the formation of Cr0.4Ni0.6 and CrN phases, associated with a nanocrystalline structure (37.6 nm) and a thicker coating (45.5 μm), resulting in polarization resistance over 290 times greater than that of untreated steel. Conversely, nitrogen-rich treatment (H75N) promoted the formation of Fe3N and Fe4N phases, achieving a dense but thinner layer (19.6 μm) with polarization resistance approximately 20 times higher than that of untreated steel. These findings underscore the effectiveness of CCPD as a versatile and scalable surface engineering technique capable of tailoring the properties of SAE 5160 steel for use in highly corrosive environments. This study highlights the critical role of optimizing gas compositions and treatment parameters, offering a foundation for advancing plasma-assisted technologies and alloying strategies. The results provide a valuable framework for developing next-generation corrosion-resistant materials, promoting the longevity and reliability of high-strength steels in demanding industrial applications.

In this work, the plasma was used in the dielectric barrier discharge (DBD) technique for modifying the high-density polyethylene (HDPE) surface. The treatments were performed via argon or oxygen, for 10 min, at a frequency of 820 Hz, voltage of 20 kV, 2 mm distance between electrodes, and atmospheric pressure. The efficiency of the plasma was determined through the triple Langmuir probe to check if it had enough energy to promote chemical changes on the material surface. Physicochemical changes were diagnosed through surface characterization techniques such as contact angle, attenuated total reflection to Fourier transform infrared spectroscopy (ATR-FTIR), X-ray excited photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Plasma electronics temperature showed that it has enough energy to break or form chemical bonds on the material surface, impacting its wettability directly. The wettability test was performed before and after treatment through the sessile drop, using distilled water, glycerin, and dimethylformamide, to the profile of surface tensions by the Fowkes method, analyzing the contact angle variation. ATR-FTIR and XPS analyses showed that groups and bonds were altered or generated on the surface when compared with the untreated sample. The AFM showed a change in roughness, and this directly affected the increase of wettability.

In this study, a combination of conventional plasma nitriding and cathodic cage plasma deposition (CCPD) at different temperatures (400 and 450 °C) is implemented to enhance the surface properties of AISI-M2 steel. This combination effectively improves the surface hardness and the formation of a favorable hardness gradient toward the core, which would benefit the load-bearing capacity of substrate. The duplex-treated samples exhibit iron nitrides Fe4N, Fe2−3N and titanium nitride TiN phases. The thickness of the hard-TiN layer is 1.35 and 2.37 μm, whereas the combined thickness of the hard film and diffusion layer is 87 and 124 μm, for treatment at 400 and 450 °C, respectively. The wear rate and friction coefficient are dramatically reduced by duplex treatment. The oxidative wear mechanism and adhesive wear mechanism are dominant for duplex-treated samples. This study suggests that the cathodic cage plasma deposition technique can attain a combination of hard film and diffusion layer. The plasma nitriding before CCPD is beneficial for attaining an adequate nitrogen diffusion layer thickness. The drawbacks of conventional TiN film deposition, such as “egg-shell” problems, can be removed.

Due to its elemental abundance, nontoxic nature, and suitable optical-electrical properties, copper oxide is a valuable p-type semiconductor for photovoltaic (PV) applications. However, synthesizing copper oxide films for PV devices with a band gap close to the Shockley–Queisser limit (1.4 eV) using a one-step deposition process is important for maximum efficiency and synthesis simplification. In this work, cathodic cage plasma deposition (CCPD) of copper oxide (CuO + Cu2O) films on glass was performed to evaluate the microstructural, morphological, chemical, and band gap changes as a function of treatment time (2 h, 3 h, 4 h, and 5 h). The samples were analyzed by scanning electron microscopy, energy-dispersive spectroscopy, x-ray diffraction, and Raman spectroscopy to identify the morphology, chemical composition, and crystalline phases of the deposited films, and diffuse reflectance spectroscopy was used to calculate the band gap width. The films showed characteristics of absorbing material in the visible region with band gap values from 1.43 eV to 1.5 eV. However, the sample treated for 3 h had a compact coating with a thickness of 1.46 µm and band gap energy of 1.43 eV, showing the applicability of the CCPD technique for synthesizing copper oxide absorber layers with an optimum band gap in a single deposition step.

This study investigates the influence of deposition temperature on the formation of diamond-Like carbon (DLC) films on AISI 4340 steel using the cathodic cylinder plasma deposition (CCyPD) technique. The films were deposited in an acetylene atmosphere at 350°C, 400°C, and 450°C, and the samples were characterized using Raman spectroscopy, X-ray diffraction (XRD), Vickers hardness testing, and friction coefficient measurements. The results indicate that increasing the deposition temperature significantly impacts the microstructure and tribological properties of the DLC films. At 450°C, the films exhibited higher hardness due to the increased concentration of sp3 carbon, which led to a denser and more rigid structure. However, a notable reduction in film thickness was observed, likely due to increased carbon deposition efficiency and structural densification. The film deposited at 400°C demonstrated the optimal balance between hardness and wear resistance. These findings highlight the critical role of temperature control in optimizing the mechanical and tribological properties of DLC films for various industrial applications.

In this work, the cathodic cage plasma deposition (CCPD) technique was applied to SAE 5160 steel, using Hastelloy cathodic cage (nickel alloy) with the aim of increasing the surface hardness and wear resistance of this steel. The deposition treatments were carried out with the samples at cathodic potential. In this work, two different atmosphere conditions were studied (75% Ну25% N and 25%H>/75%N.), at a temperature of 450°C during 4 hours. The coatings formed were analyzed using X-ray diffraction, optical microscopy, Vickers microhardness and microabrasive wear tests. Both treatment conditions favored the formation of coatings with high microhardness and excellent adhesion to the substrate. The treatment carried out in the most hydrogenrich atmosphere (75%H/25%N2) showed greater layer thickness and superior wear resistance, with a reduction of around 65% in the worn volume.

TiO2 (titanium dioxide) nanoparticles have been widely used in various industrial sectors, such as photodegradation and photocatalysis systems, photovoltaic cells and biomedical applications, exhibiting osseointegration, bactericidal, antitumor and cell differentiation properties. These nanoparticles can be used in the form of powders, crystals, nanorods, nanotubes and thin films. In this sense, as an alternative to improve the surface properties of AISI 304 stainless steel, TiO2 nanoparticles (powders) were incorporated into thin films obtained through duplex plasma treatment (conventional plasma nitriding followed by cathodic cage plasma deposition) in order to evaluate the mechanical properties, wettability and bacterial response. The thin films were characterized using Grazing Incidence X-Ray Diffraction (GIXRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), and Rockwell C adhesion, Vickers microhardness, surface roughness (Ra and Rg), wettability and bacterial adhesion tests. The treatment was efficient in depositing coatings incorporating TiO2 nanoparticles on the surface of AISI 304 steel, obtaining thin films with good layer uniformity and excellent adhesion to the substrate. All the treated samples had a higher surface microhardness than the untreated sample. After the treatments, the films showed an increase in surface roughness which corroborated in obtaining more hydrophilic surfaces, with contact angle reductions of up to 88.94%, and lower bacterial adhesion activity, showing reductions of up to 78.42%. The set of attractive and promising properties obtained with the deposition of these films may arouse interest in their use in biomedical applications, such as their possible use in metal prostheses.

AISI 304 stainless steel has a wide range of applications, including biomedical applications such as prostheses, implants and surgical tools. In this work, thin films of Ti-Nb-N were deposited on AISI 304 stainless steel using the cathodic cage plasma deposition technique. Two cage arrangements were used and the treatments were carried out at 350, 400 and 450 °C in order to evaluate the morphology, adhesion, wettability and biological properties of the deposited films. The samples were characterized using Raman spectroscopy, x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy and Rockwell C adhesion, wettability, bacterial adhesion and cell proliferation tests. The films obtained had a uniform appearance with a good distribution of titanium, niobium and nitrogen on the surface. All the films showed adhesion to the substrate within acceptable failure criteria. The treated samples showed greater hydrophilicity and lower bacterial adhesion compared to the untreated sample, these results being better for the cage arrangement formed by the niobium cylinder and titanium lid (NbTi). All the treated samples showed greater cell proliferation than the untreated sample, with increases of around 372% and 367%, respectively, for the NbTi450 and TiNb400 samples.

This article provides a brief review of titanium-based thin films deposited using physical vapor deposition (PVD) processes on various types of substrates, and also contains a topic dedicated to the deposition of these films using the cathodic cage plasma deposition (CCPD) technique. Thin films play a crucial role in a variety of industrial applications, including corrosion protection, wear resistance and biomedical applications. Titanium is a widely used material due to its excellent corrosion resistance, high hardness and biocompatibility. PVD methods stand out due to the high deposition rate, lower temperatures and treatment times compared to chemical vapor deposition (CVD) processes and have been commonly adopted to deposit titanium thin films on various types of substrates due to their ability to produce high quality coatings with good adhesion and uniformity. The fundamental principles of the cathodic cage plasma deposition PVD process and a review, over the last five years, of the main research articles in the PubMed, SciELO, ScienceDirect, Scopus and Springer Link databases, highlighting the main deposition parameters, deposition technique used, results and applications of titanium-based thin films deposited on various types of materials are covered in this article.

Due to its good corrosion resistance and ductility, 304 stainless steel (304 SS) is a material of choice for various applications. However, its hardness and wear resistance are often not low enough to cater to the demands of highly demanding fields. It is possible to upgrade these characteristics and the life and performance of the parts processed from this material using an established technique, plasma nitriding. This study made a significant contribution to the field by examining the impact of plasma nitriding on 304 SS samples subjected to different degrees of prior rolling, ranging from 0% to 50%. The authors sought to deepen their knowledge of the role of this premodification in nitrogen uptake, the formation of the nitrided phase, and, consequently, the mechanical properties. The characterization methods included X-ray diffraction, scanning electron microscopy, energydispersive X-ray spectroscopy, Vickers microhardness, and corrosion resistance tests. The resultant findings confirmed a priori the necessity for a pre-rolling forming pre-treatment of the steel to modify its microstructure and, as a result, the efficiency of the plasma nitriding treatment. As determined by the study, a higher rolling degree before nitriding results in a higher number of phases that are generated nitrided, and consequently, a higher hardness, wear, and corrosion resistance of the samples with a higher rolling degree is much improved.